The invention relates to a method for producing adhesive-bound book blocks composed of gathered signatures. With this method, the individual signatures forming a non-bound book block are supplied to an opened conveying clamp for an adhesive binder while positioned on their spines in a transfer section and are subsequently held in place by the closed conveying clamp along the flat outer surfaces. The invention furthermore relates to an apparatus for realizing the method.
For an industrial-type production of adhesive-bound printed products, for example magazines, catalogs, paperback books or similar products, printed sheets or signatures are gathered during a first step to form non-bound book blocks. Subsequently, the spinal region of these book blocks is processed, for example by milling, and is then provided with adhesive in a perfect binder, whereupon the book blocks are bound and/or provided with a casing. The position of the printed image on the sheet or the signature is determined in reference to the edges of its spine and generally also in reference to the top edges. Thus, if all signatures of a non-bound book block are aligned with these reference edges, then all pages within a book block are also aligned relative to each other. According to known prior art, signatures positioned inside a conveying channel are gathered and aligned with the aid of circulating conveying elements. A gathering device of this type is disclosed, for example, in European patent document EP 1 726 552 A1. Following the gathering of the signatures, the non-bound book blocks having spine edges that are aligned transverse to the conveying direction are then rotated by 90°, so that the spinal edges are aligned parallel with the conveying direction. In a further step, the non-bound book blocks are positioned upright on the spines, so that their flat sides are perpendicular and, in this position, are inserted from below into the conveying clamps of the perfect binder. A method of this type is disclosed in the applicant's own, European Patent No: EP 1886832. During the complete binding process, the book blocks are clamped into the circulating conveying clamps, wherein their flat sides are positioned perpendicular and parallel to the conveying direction and the spine areas project slightly from the conveying clamps, in a downward direction. The positioning accuracy for the book blocks in the conveying clamps is decisive for the quality of a book.